The decomposition of any material by microorganisms(noun)
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Use "biodegradation" in a sentence
"FTC brought an enforcement action: Most trash ends up in landfills, which are designed to avoid biodegradation."
"• Lisa P. Jackson, Administrator, EPA said at the May 24 White House press briefing “Our tracking indicates that the dispersants are breaking up the oil and speeding its biodegradation, with limited environmental impact at thistime.”"
"And second, in a section called The Fate of all Hydorcarbons, a study done in late September concluded that "most of the initial biodegradation in the plumes involved gaseous hydrocarbons (propane and ethane), rather than oil.""